Catalytic conversion of hydrocarbon oils



Mrch '9, 1943. w, KAPLN CATALYTIG CONVERSION O y HYDROOARBON OILS Filed Oct. 2, 1939 2 Sheets-Sheet l 2 INVENTOR n//LL//IIM /f/Vlfa/,g/vrl March 9, 1943. w. KAPLAN CATALYTIC CONVERSION OF HYDROCARBON OILS Y 2 Sheets-Sheet 2 Filed oct. 2, 1959 een@ Maf-e194@ f ,A 2.313.346

UNITED t STATES Parri-:NT ori-"ica cA'rALY'rIc CONVERSION or' nrpnoe CARBON oms .William Kaplan, ltllalverne, N. Y., assigner to Y* Cities Service Cil Company, New York, N.'Y., a' corporation of Pennsylva Application october z, 1939, serial No. 297,452

i 6 Claims. (01196-52) c v This invention relates to an improved process matics, whichcontribute, most to the anti-knock for manufacturing cyclic and aromatic hydrovalue. i l carbons, and more particularly to a catalytic proc- In commercially used vapor phase processes', less for the conversion of hydrocarbon oils or gases which require 'a vaporizable type charging oilfor into cyclic and aromatic hydrocarbons. The the heating zone, unless a separator is interposed present application is a continuation-in-part of for separating heavy asphaltic constituents, the

the applicants pending application Serial No. gasoline product contains more aromatics than 264,693, led March 29, 1939, for Manufactur the "mixed-phase gasoline product, and this is of alkylated benzene hydrocarbons. partially reflected in a higher anti-knock value.-

10 The percent aromatics will generally range from manufactured from petroleum by various proc- 5% 'to 30%J depending mainly on thejtype of esses which have generally involved either; Y(a) charging stook- Generally, the gasoline will preoperation at extremely high temperatures of the' dominate in olenic unsaturates, ranging from order of 1200 F. to 1400" F. or higher, or (b) op- 40 %V to 70%, which is thev chief reason for the ineration at more moderate vapor phase tempera- 15 creased anti-.knock value. However, even when tures (950-1l00 F.) for an extremely long pe. the oleiinic unsaturates are inexcessof 70%, the riod of time. Inboth types of operation, the proanti-knock value will rarely exceed about 80 ocduction of hydrocarbons in the gasoline boiling tane number-C. F, R. These processes, which range is very low, while the loss ,as iixed'gas is operate et moderate conversions per pass (10% to 30%), willproduce a gasoline high in oleflnic extremely high. Although the fixed gas loss is 20 y lower in the long-time digestion type process than unsaturates when the pressureis reduced, or when the temperature is increased. For example, op-

in the extremely high temperature processes, the loss in the former type is generally about 40% or Hating at 10W pressure (e. E. 30 t0 75 1bS.)"and higher. Inboth types ofl operation, the cracking high temperature (e. g. 1 100 to 1150 F.) ,the liromust be carried substantially beyondthe point portion of olefine unsaturatesinthe gasoline'boilof maximum gasoline recovery. In addition, the ing range will amount to 65 to '10%, while at high gasoline product from the former type contains pressure (200 to 500 lbs), and lowertemperature sufficient olefins and diolens to'render the puri- (950 .to 1000 F.) the Olenic unsaturates will ilcation treatment very diicult or expensive by amount t0 "45 t0 55%. The length ofrcracking present treating processes. Ask a result, thesel 01 digestion has Very little 111111121108 011 the prftypes of operation have' not been commercially portion of the various hydrocarbons contained in adopted the gasoline when these processes are operatedy at moderate conversions per pass, i. e. 10% to'35% f The present process is free of these disadvan# tages because a highly aromatic gasoline can be Per Pass, Since there 'iS an apparent equilibrium produced at moderate conversion per pass, thus distribution of the various hydrocarbonsforvany obviating the neessityfor going beyond the point given stock and set of operating conditions. of maximum gasoline yield. As a result, the fixed As a general average, present `dat' Vapor Phase commercial processes will produce, a Y gasoline gas loss is substantially lowered. The present process also operates in the lower vapor phase product Containing about to 55% unsaturates temperature range so that the percentage of detrio or oleiins, about 10-20`% aromatcs, with the ball mental oleiinic and diolefinic content is very low y anco comprising naphthenes and paranlns; vThe thus assuring ease of purification withv present distinguishing characteristics of the present proc-' f treating processes, ess is the production of a highlyv aromatic prod- When topped crude or gas oilis cracked under uct, even when operating at moderate conversion. mixed-phase conditions, as practiced by many 45 per pass. Instead of containing a relatively large present-day commercial processes, the gasoline amount of olefins and a small amount' of aro-` product is low in aromatics, ranging from 5% to. matics, the presence of the catalyst*,activa-tedv 25%; varying with the type of charging stock and carbon, eliects a reversal of this apparentequil y' operating conditions. Similarly, the percentage llblum dlsmbution. and results in the PIOdUCfiODS of olennic unsaturates will range from 15% to 50 0f e relatively large' proportion of aromaticsand 35%, while the balance will consist of naphthenes a small proportion of olens in th Aga e and parafflns. It is generally recognized that ing range. Although the exactfm ha these processes produce a gasoline of relatively this transformation is'not" denitely'k low anti-knockvalue (60 to '10 octane number-C. believed thepresence of the activ F. R.) chiefly because of the deficiency in arofects'a cycli'zation of'either'oleilns i( `Aromatic and cyclic hydrocarbons have been both; particularly those containing six to nine carbon atoms (whether straight chain or branched chain). As a result, the gasoline product of the present process will generally contain a small proportion of unsaturates and upwards of 40% aromatics, depending on the amount of activated carbon used.

While the production of a;high1y aromatic product of high anti-knock value (80 octane number-C. F. R. or higher) is the most noticeable eiect of the present process; other advantages will be noted when practicing the process. For example, the cracking reaction will apparently proceed with greater ease; that is, at-a given temperature, the cracking per pass Will be somewhat higher. lIn addition, the heat required for the cracking reaction is reduced considerably so that less heat input is required in the soaking tube bank in order to maintain a given temperature, ythus effecting a reduction in fuel. consumption.

The primary object of this invention is therefore to provide an improved process in which petroleum hydrocarbons are catalytically converted by the action of activated carbon into cyclic and aromatic hydrocarbons, including those with side chains. l

Other objects are to provide a process for producing a gasoline of high antiknock value; to provide a process for converting olefins and/or paraiiins into cyclic hydrocarbons; to provide a process in which the conversion reaction is accelerated; to provide a process in which the fuel consumption is materally lowered; to provide a process in which the proportion `of aromatics 1s increased even when operating at moderateconversion per pass; to provide a process in Whlch aromatics can be produced from all types of petroleum hydrocarbons, including gasoline and .normally gaseous hydrocarbons;` to provide a process for converting olens to aromatics; to provide a process which will produce a gasoline product which canbe easily treated; and to provide a process for producing aromatic hydrocarbons in which the xed gas` loss is materially lower than usual.

Accordingly, the improved process of the present invention comprises in general the steps of passing a vaporizable petroleum distillate'stock such `as gas oil, o-r kerosene, through the heating coil of a pipe still furnace in which it is vaporized and heated to a temperature of from 950 to 975 F., intimately mingling with the vapor stream a predetermined proportion of activated carbon, digesting the mixture for a period of time sufficient to effect the desired conversion,

and recovering the desired products. While gasoil and kerosenehave been mentioned, the process is adapted to conversion of naphthas and straightrun gasoline, as wellas butane and/or propane fractions, by effecting the conversion at more elevated temperatures. In fact, the .process is easily adapted to almost any type of vapor phase cracking or so-called polymerization process by making the necessary provisions for introducing the activated carbon `atari appropriate point in the digesting step. The pressure -may be low (30to 75 lbs.), or elevated pressures may be used (100 to 500 lbs), although the lower pressures will generally require higher operating temperatures for a given furnace structure. With gas oil, the pressure at the heating coil outlet is preferably from 150 to 300 lbs. per square inch, at a temperature'of 950 to 975 F. Although it may be possible vto eiect this heataromatics desired in the final product, higher quantities causing increased propo-rtions of aromatics` Naturally the velocity and particle size of theactivated carbon should be controlled so that the catalyst will be maintained in suspena once-through process. The digestion, if done in'a coil, is preferably c onducted at 150 to 250 lbs. pressure with a final temperature of 1000 to 1025 F. when using about ten pounds of actiable separating device, the vapor products suddenly chilled to a temperature of from 700 to 800 F., and the resulting separated vapor products subjected to a fractionation operation for the recovery of the desired hydrocarbons.

Various other features, objects, and advantages of the improved process of the present invention will be apparent to those skilled in the art from the following more detailed description thereof, taken in connection 'with the' accompanying drawings in which:

Fig. 1 is a diagrammatic elevational view of an assembly of` apparatus elements particularly adapted lfor carrying out the essential features of the improved process.

Fig. 2 is a view similar to Fig. 1 showing a modified form of apparatus for carrying out the improved process with certain modifications in the operation.

Referring to the apparatus shown in Fig.V 1 of the drawings, the oil charging stock, such for example as a gas-oil distillate, tol be converted into cyclic and aromatic hydrocarbons, is introduced into the Aapparatus through a line 2, and forced by means of a pump 4 mounted therein, at a pressure of from 400 to 600 lbs. per square inch, through a heating tube bank 6 mounted in a pipe still furnace V8. the tube bank 6 is heated to a discharge temperature of approximately 950 F., and the tube bank is of suliicient length to permit complete vaporization of the oilfand effect from 5% to 10% conversion of the oii to gasoline.

The hot oilproducts from the tube bank 6 are conducted through a vapor line I0 in which the activated carbon catalyst is introduced and mixed therewith. The activated carbon is4 conducted from a supply chamber I2 through a valved conduit I4, a rotary feed and measuring valve I6 and a valved conduit I8, into the line IIJ. The activated carbon catalyst is discharged into the stream of vapors in the line IU at a controlled rate and carried into and through reaction coils or tube banks 20 mounted in a pipe still furnace 22.

The valve I6 may beA of any suitable type coinmonly used for feeding nely divided materials,

such vas the activated carbon catalyst, at a con After the digestion l to convert the oil constituents into cyclic and 35 trolled rate. The valve may comprise a rotary through a cracking coil 52 mounted in a pipe s till plug provided with a pocket for receiving the furnace 54. The recycle gas oil is cracked at a activated carbon from the line I4. At every 10- high temperature for a substantial period of time tation of the plug the material deposited in the in the coil 52 to produce finely divided carbon pocket from the line I4 will be discharged into 5 which has been found to be very active.v The the line I8. The valve is vapor-tight and prefproducts resulting from this cracking operation onducted at a temperature of approximately erably provided with a valved vent line 24, so are c that any vapor picked up by the pocket in pass- 1100 F. through a valved transfer line 56 into ing the line I8 will be vented through the line the line i0 to supplya-nd suspend the desired 24 Without disturbing the material flowing 10 proportion of catalyst in the vapors passing through the line I4. The rotary plug in the valve through the line I0. Suiiicient catalyst will be I6 may contain a .number of pockets spaced supplied for most operations by regulating the around the circumference of the plug in order proportion of recycle gas oil in the line 50 so'that to assure more even distribution of the carbon in it comprises approximately of the charging the vapor stream. The feed rate of the catalyst 15 stock supplied to the pipe still furnace 8 through is controlled by the speed of rotation of the plug the line 2. In providing a suspension of actiof the rotary valve. vated carbon in the line I0 from the furnace 54, The vapor stream passing through the line I0 the cracking in furnace 54 must be severe enough th approximately ten to form a substantial quantity of activated Vcaris preferably suppliedwi U pounds of activated carbon catalyst per barrel 20 bon; and the velocity must be sufficiently high in of charging stock supplied to the tube bank 6, order to keep the carbon suspended in the vapor although from 3 to 25 lbs. of catalyst per barrel stream. Carbon produced in this-manner has may be used for certain specific stocks or prodbeen found to be particularly effective in proucts desired. The mixture of vapors and catalyst ducing the desired catalytic reaction. Although passing through the tube banks are raised in 25 it is diicult to describe the activity in precise temperature to approximately 1010 F. as an outterms, one test'for determining the reactivity of let temperature. The gasoline constituents enthe carbon is to note its reaction when in contact tering the tube banks 20 will normally contain with air. For example, carbon produced in the approximately 50% to 60% of unsaturated olefin above described manner, when separated, cooled, type hydrocarbons, a small proportion of aroand allowed to come in contact with air in a conmatic hydrocarbons, a small proportion of naphtainer, will soon become red hot, glowing red thenes, and the remainder saturated hydrocarbelow the apparent black upper surface. This bons. The coils 20 are preferably of such length heat liberation is apparently due to the extremely as to carry out the desired catalytic reactions high adsorption of air. Ifthe container is loosely covered, the hot zone will gradually travel from aromatic compounds. the to'p to the bottom of the container, although The reaction products, including the suspended f very little` carbon will be burned away. If the catalytic material, are discharged vthrough a container is not covered, the carbonwill gradvalved transfer line 26 and immediately chilled ually disappear. Oil men.. particularly those to a temperature of approximately '100 F., by the 40 familiar with vapor phase processes, will recogintroduction of a quenching medium such as gas nize this type Of 09110011- oil, water, or other relatively cool material, In accordance with the modified form of the through a line 28, in which is mounted a pump. process of the present invention carried out in The resulting relatively cool mixture is disthe apparatus shown in Fig. 2, the oil stock to be charged into the lower portion of a tower 30, converted is introduced into the apparatus in which the heavier ends and carbon catalyst through a line and forced by means of a pump are separated, and from which they are withmounted therein through a heating coil 62 set drawn through a valved line 32. The fractionv in the combustionv space and under the roof ofa ating tower 30 is operated under suitable prespipe still furnace 64. In this coil, the oil is stantially the same conditions sure and temperature conditions, so that the uheated under sub products boiling below approximately 450 F. are as those described for the coil 6 in Fig. l. The conducted in vapor form through a valved vapor hotvapor products are conducted from the coil line .34, the condensable constituents condensed 62 through a line 66, and therein intimately in a condenser 36, and all overhead productsV mingled with activated carbon `as a catalyst. conducted through a line 38 into a separator 40. 55 The resulting mixture is then conducted through The normally gaseous constituents are separated a reaction coil 68 mounted in the convection secout in the separator 40 and discharged through tion of the pipe still furnace 64, after which the an automatic pressure valve controlled line 42. resulting products pass ,through a transfer line The fractionation in the tower 30 may be con- 10 and a valved line 12, into the upper portion trolled in part by'conducting condensate from 60 of an enlarged reaction chamber 14, and then the receiver 40 through a line 44, by means through a valved line 16 and a portion of the line of a pump mounted therein, into the upper 12, directly into a cyclone separator 1B, or the portion of the tower A3l) where it is used hotv products may pass directly from the line 10 as reux. The overhead condensate prodv to the left in the line 12, and into the cyclone uct is removed from the receiver 40 through a 65 separator 18, without passing through the envalved line 46. Various higher boiling products larged reaction chamber. f may also be recovered from the tower 30 and- Where theentire reaction is carried out in the removed as side streams through the valved coil 68, this coil should be sumciently long (from lines 48. 1000 to 4000 feet depending on the vapor veloc-` The activated carbon catalyst may be supplied 70 ity) to give a time reaction for effecting the de. to the line I0 by any means other than that desired conversion of theol to aromatic and cyclic n scribed above. For example, the Acatalyst. may hydrocarbons. Where the colli is usedalone, theV be manufactured by introducing a recycle gas oil temperature conditions will be the same as those through a line 50, and forcing it at a suitable described in connection with Fig. 1'of the draw- PleSSure by means 0f a pump mounted therein 75 ings, but where the enlarged reaction chambe to a temperature of from 'I4 is used in the cycle, the coil 68 may be relatively short. When the reaction chamber 14 is employed, the temperature ofthe products in line 10 may range from approximately 990 F to 1020 F. which temperatures are suiciently high to cause the desired reaction in the chamber 14. Regardless of whether or not the reaction chamber 'I4 is utilized, the reaction products introduced into the cyclone separator 18 through the line l2 will contain all of the suspended activated carbon catalyst which will be separated out by the cyclone separator.

Initially, the activated carbon supplied to the line 66 is withdrawn froma supply chamber 80 through a valved conduit and fed by means o1' a rotary valve 82 and a line. to the line 8B in the manner described above in connection with Fig. 1 of the drawings. After the operation has been conducted for some time, activated carbon will be collected inthe bottom of the cyclone separator 10 from which it may be fed through a valved line I6 to the rotary valve 82 and the line y il, thereby replacing the supply from the chamber I0. In the operation of the rotary valve 82 any vapor entering the valve may be readily vented into the cyclone separator through the vent line 88. The utilization ofthe activated carbon lin carrying out the reaction does not change its activity, but for some unknown reason it appears that the high temperatures actually maintain or increase its activity.` Therefore, the continuous recycling of the catalyst may be carried out almost indefinitely. If desired, however, any of the used catalyst may be removed from the cyclone separator through a valved line 90 or any deficiency may be supplied from the supply chamber 80. V

The vapor products separated from the catalyst in the cyclone separator i8` are discharged into a valved line 92 and immediately quenched 600 F. to 700 F. by a relatively cool fluid such as those mentioned above, introduced through a line 94. The resulting products are conducted to the lower Aportion of a fractionating tower 96 which is operated in the same manner as the tower 30 of Fig. l. The heavy bottoms which in this case are substantially free of any of the carbon catalyst are discharged through a valved line l98 while the overhead -vapors are conducted through a valved line |00, subjected to condensation in a condenser |02, and then conducted through a line |04 into a reciver |06. A portion of the condensate separated out in the receiver |06 may be used as reflux in the top of the tower 95 by conducting it through a line |08 by means of a pump mounted therein. The overhead condensate product is discharged from receiver |56 through a valved line I0, while the uncondensed gases are discharged therefrom through an automatic pressure valvecontrolled line H2. Side stream products of higher boiling point than that collected inthe receiver |06 may be withdrawn from any point in the tower` 96, as for example,through valved lines ||4. When `the side stream products, discharged for example through the valved lines H4, do not contain substantial proportions of desirable cyclic and aromatic hydrocarbons, they may be reprocessed in the operation by passingveither or both of them through valved line ||6 by means of a pump mounted therein, and introducing them into the charging line 60 to the coil 62.

The activated carbon catalyst to be supplied to the line 66- maybe formed directly as in the ful products.

case of `the operation shown in Fig. 1, by conducting a recycle stock such as recycle gas oil through a valved line ||8 by means of a pump mounted therein, and passing it through a coil |20 mounted in a pipe still furnace |22 where it is heated under the same conditions as those described in Fig. 1, for the furnace 5I. The resulting highly heated cracked products are then conducted through a transfer line I 24 directly into the line 66 to supply the activated carbon catalyst. When the catalyst is supplied directly in this manner, the activated carbon separated out in the cyclone separator 18 may be entirely discharged through l of it returned through the rotary valve 82'. T'he direct supply of activated carbon as from the furnace |22 is of particular advantage where the carbon separated out in the cyclone separator and removed through the line may be mara decolorizing agent in other industries.

The recycle gas-oil for the furnace |22 may be obtained from line IIB after the operation has been started, by conducting it through valved connecting line I 26 into the line H8. In the manufacture of activated carbon by this procedure, recycle gas oil is preferred because the carbon to hydrogen ratio is much higher than that for straightrun more easily converted to a substantial degree into finely divided activated carbon.

.The overhead distillate as well as the side stream .distillates removed from the towers 30 and 96 may be fractionated into rather narrow fractions for the recovery of more or less individual aromatic hydrocarbons are particularly suitable for various industrial purposes. Theoverhead product will contain primarily benzene derivatives, many of which will be side chain products suitable for use as solvents Some of compounds are obtainable from the side streams l and are valuable for use as intermediates in the manufacture of dyes, lubricants, and other use- 'I'he overhead product of course maybe used as a gasoline blending agent for increasing the octane rating of relatively poor gasollnes, because it contains large proportions of` side chain aromatic hydrocarbons.

The results obtained from the carrying out of the process may be illustrated by reference to the conversion of a heavy gasoil charging stock. This gas-oil was introduced into a furnace such as the furnace 8 and subjected to a temperature at the outlet of about 950 F. and an outlet pressure of 275 poundsl per square inch. Sufficient cracking was accomplished in this operation so that the fraction boiling below 450 F. comprises approximately 16% from the furnace. Activated carbon having a` neness of approximately 150.1nesh was introduced into the vapor stream at the rate of about 8 lbs. per barrel of charging stock and the resulting mixture'subjected to further heating for a relatively long period of time at a temperature averaging about 980 F. at the outlet of a furnace such as the furnace 22. The outlet pressure was maintained at approximately lbs. per square inch. As the products discharged from the last heating operation they were quickly chilled to a temperature of 650 F. by the introduction of gas-oil.

The products remaining in vapor state after the chilling operation, were fractionated, and an the line 90, or only a portion oils, and it for this reason, is

or fractions which of the products discharged f drocarbons by the Egloff & Morrell method described in Industrial & Engineering RChemistry, Vol. 18 (1926) pages 354 to 356. A` refractionation of the overhead distillate showed the presence of a large number of aromatic hydrocarbons such as benzol, toluol, xylol, as well as more complex side chain benzene and naphthene derivatives. i Y

When the process of the present invention is carried out for the production of relatively high percentages of aromatic hydrocarbons inthe overhead products, the side streams withdrawn through the lines 48 and Il4- contain considerable proportions of cyclic and aromatic deri a.- tives of relatively high boiling point. The fraotionation of these side streams discloses the pres\ ence of naphth-alene, alkyl naphthalenes, an-

thracene,phenanthrene, diphenyl, diphenyl methane, dibenzylV and hydronaphthalenes. Even when a moderate content of aromatic hydrocarbon compounds is obtained overhead from the tower 30 or 96, the side streams will contain some of the above compounds. Saturated cyclic hydrocarbons are also found in the products of the reaction such as alkyl cyclohexanes.

The activated carbon catalyst appears to act very eiectively in the conversion of unsaturated Y hydrocarbons into aromatic compounds because in the example given above, the overhead distillate showed practically no unsaturated hydrocarbons of the olefin or diolefin type. The normally gaseous hydrocarbons separated out for example in a separator such as 40 was also low in olens, particularly C3 and C4 olefins. The improved process therefore is particularly eiilcient in avoiding high gas losses which reach 40% or higher in some known processes employed for the production of aromatic hydrocarbons.

In carrying out the process of the present invention for the conversion of normally gaseous hydrocarbons such as propane, butane, corresponding olens or mixtures containing these hydrocarbons, as well as cth-ane and ethylene, the charging stock either in liquid or gaseous phase is preferably heated in-a stream in the coil of a pipe still furnacato a temperature of approximately 1100'o F. At this point the finely divided activated carbon catalyst is intimately distributed therein in the desired proportion such as the range of proportions described above.

` The resulting intimate mixture is continued in the stream through a digestion zone where the intimate mixture is maintained for a period of time suil'icient to effect a substantial conversion to gasoline boiling range hydrocarbons. The gasoline product under these conditions will contain at least 40% of aromatic hydrocarbons and may contain as high as 85% of aromatic hydrocracked products produced by the steps of heating a hydrocarbon distillate in a heating zone under temperature, pressure and time conditions suiiicient to eiect partial conversion thereof into a mixture of cracked products low in aromatic hydrocarbons containing at least approximately 50% of unsaturatedolenic hydrocarbons, which i comprises intimately mixing a nely divided activated carbon catalyst with said mixture `of highly heated cracked -products and passing the resulting mixture through a reaction zonein which it is maintained at a temperature of from 970 to 1050F. for a considerable period of time adapted to eonvertfsaid products into a nal carbons. Normally gaseous olens such as butylene are satisfactorily converted to aromatic hydrocarbons at some what lower temperatures, such for example as 1050 F.

Various modifications of the improved process of the present invention may be made without departing from the spirit and scope of the invention as will appear Vto--those skilled in the art. Such modifications are contemplated within the invention as dei-ined by the accompanying claims.

Having thus described the invention in its preferred form, what is claimed as new is:

1. The process of manufacturing aromatic hydrocarbons from a mixture of highly heated product containing a relatively high percentage of aromatic hydrocarbons, maintaining the active carbon'. catalyst in intimate dispersion in the mixture in the reaction zone, and separating the desired aromatic hydrocarbon fractions from the 20 flnal product.

2. The process rof manufacturing cyclic and aromatic hydrocarbons from a mixture of highly heated cracked products produced by the steps of passing a petroleum oil distillate in a confined stream of restricted cross section through a heating zone wherein the distillate is vaporized and heated to a' discharge temperature of app oximately 950y F., and wherein the distillate in said stream is heated for a sufficient length of ime at cracking temperatures to effect partial \\conversion of the distillate to unsaturated olenic constituents, which comprises mingling an activated carbon catalyst with said highly heated products and passing the resulting mixture through a reaction zone in which heat is applied to the said resulting mixture and in which the mixture is maintained at a temperature oi from 970 to 1050 F. for a sufiicient period of time to produce a product containing a relativelyhigh percentage of aromatic hydrocarbons, disc arging the resulting reaction products' with the atalyst from said reaction zone, separating the atalyst from the reaction products and fractionating the reaction'products to recover the desire aromatic hydrocarbons.

3. The process oi manufacturing aromatic hydrocarbons from mixture of highly heated cracked products produced by the steps of heating a parafnic petroleum distillate in a heating zone under temperature, pressure and time conditions sucient to efiect partial conversion of` the `distillate into a m' ure 'of cracked products containing unsaturated Noleflnic hydrocarbons, which comprises intimately mixing a finely divided activated carbon catalyst with said mixture of highly heated cracked products and-passing the resulting mixture through a. reaction ,zone in which it is maintained at a temperature of approximately 1000` F. for a considerable period of time adapted to convert said products into a nal product containing a relatively high nic hydrocarbons, which comprises adding to the said mixture of highly heated cracked vapor `high percentage products a relatively small proportionkof a finely divided catalyst consisting of activated carbon, and subjecting the resulting mixture in a iio ing stream in which the nely divided activated carbon is suspended to high temperature reaction conditions of from 970 -to 1050 F. adapted to produce a iinal product containing a relatively of aromatic hydrocarbons. i

5. The process of manufacturing Vcyclic and aromatic hydrocarbons, which comprises intimately mixing a finely divided activated carbon catalyst with a hydrocarbon product which is relatively low in cyclic and aromatic hydrocarbons and relatively high in oleiinic hydrocarbons and'which contains from about`5% to 16% of gasoline boiling range hydrocarbons, passing the resulting mixture in a connned stream of` restricted cross-section and maintaining the same at a reaction temperature of about 1000 F. for a sufficient time to produce a conversion product which is relatively low in oleiinic content and relatively high in cyclic and aromatic hydrocarbon content. maintaining said catalyst in inti. mate dispersion in said stream, separating the y'temperature `of from 970 carbon catalyst from the stream of lconversion products and recovering the cyclic and aromatic hydrocarbons.

6. The,l process of manufacturing aromatic hydrocarbjons from a mixture of highly heated crackedl products produced by the steps of heating a pqeitroleum distillate in a heating zone under temperature, pressure and time conditions sumcient to eiTect partial conversion of the distillate into amixtu're of cracked products containing a subs/tantzial proportion of unsaturated oleiinic hydrocarbons, which comprises intimately mixing/v a finely divided activated carbon catalyst with saivci mixture of highly heated cracked products and passing the resulting mixture through a; reaction zone in which it is maintained at a to 1050 F. for a considerablle period of time adapted to convert said products into a nal product containing a relatively high percentage of aromatic hydrocarbons, and separating the desired aromatic hydrocarbon fractionsfrom the final product.

WILLIAM KAPLAN. 

